n4zou

I was given some Bamboo by a neighbor who considers it a weed. First thing I did was find a section with an interior large enough a Fraen lens and holder would fit. I found one and cut it slightly longer than 2 inches. I then measured another section that would tightly fit inside and cut a narrow section about 1/8 inch. I used some glue to hold it tightly in place. this would become a stop for the lens. Here are a couple of photos ready for the copper heat sink, LED, and Lens.

I cut some clear plastic to protect the lens. A little glue holds it and seals the front.


I already had the Lens, LED, and heat sink.


A bit of toilet paper cardboard wrapped and taped around the lens holder prevents rattling.


Lens, LED, and Heat sink slides right in.


Front of headlight.


A little weather sealing RTV around the edge of the heat sink will keep the LED assembly firmly in place which I will apply later.

mrbubbles

Artistic, but how are you going to dissipate the heat? Unless you aren't planning to run it very high.

varuscelli

n4zou

I'm using copper sheet metal as the heat sink and powering it from my dynamo. I've been running that LED in a 1" PVC pipe coupler the same way for a couple of years with no over heating problems. My dynamo tops out at 700mA at speed so the LED is not being run at it's full 1000mA current rating so heat production is reduced.

varuscelli

Very inventive concept, Scott. And I hope you took the "fire extinguisher" as the joke it was intended to be. I meant that in no way to dismiss your headlight invention. I think it's a very neat idea, and in the least a partial "going green" device...

I've always been somewhat fascinated by what could be done with bamboo and have had at times in the past some pretty big (diameter-wise) pieces I never quite did anything with except to admire.

n4zou

Finished my headlight today just in time for Critical Mass tomorrow.
I was going to attach it to the bike with a couple of conduit hangers but after putting a coat of Polyurethane on it that conduit hanger would have been too ugly. I used a 1" corner bracket, hemp twine, and more Polyurethane to provide an attachment point. It turned out rather nice.

Cave

So - you think it needs a heatsink, but you' ve wrapped it first in cardboard, then bamboo?

Unknown Cyclist

This might not be obvious to everyone, but cardboard is actually a pretty good insulator.....

ModoVincere

drill some holes on the bottom for airflow....that should allow the heatsink to do its job better and still keep water from entering.

n4zou

The back of my copper heat sink is open so the little heat generated can easily escape. I've run this same LED and lens assembly in a 1" PVC pipe coupler with no heating issues. It's getting powered by my dynamo so it's running at 70% of rated maximum drive current of 1000mA. This reduces generated heat by almost half. I did a 3 hour ride last night just to make sure it would hold up for CM tonight. It worked fine.


Here is the old PVC pipe coupler arrangement.

ModoVincere

understand...but enhancing airflow across the heat sink could only be helpful. Would not require much, maybe a 1/8" hole or 2.

do you have any issues with moisture causing shorting problems since it looks like 1/2 your electronics are openly exposed.

n4zou

The rectifier diodes and capacitor are encased in epoxy during the manufacturing process and rain water is actually a good insulator. Theres really nothing that fresh water or even soapy water is going to harm.
I ran this rectifier for a couple of years with no harm and still use it on another bike.

A little thermal glue seals the the front clear plastic over the lens and the edge of the heat sink. A trick I found which works very nicely to remove all moisture prior to sealing is to wrap the object to be sealed in a cotton shop towel and bury it in new unused cat litter for a couple of hours. This will remove all moisture. Then quickly assemble and seal with thermal glue like this FUJIK Silicone Thermal Glue. It's easily removed if you need to open up the sealed assembly later.
https://www.dealextreme.com/details.dx/sku.4579

SlimAgainSoon

Man, that is cool!

Need to make an organic hanger -- all that steel doesn't do it justice.

cyccommute 

That is soooo Gilligan's Island

n4zou

Wait till you see the LED taillight I'm building! Two packs of these.

https://www.dealextreme.com/details.dx/sku.9075
and more Bamboo.

varuscelli

Yeah, I've been thinking the whole time how proud The Professor would be. And it would be a heck of a way to impress Ginger and MaryAnn, thus moving the inventor up the list of the island's Most Desirable Males.